Conventionally, a thermal conducting sheet filled with a thermal conducting filler such as silicon carbide and aluminum hydroxide, which is highly thermally conductive to an acrylic resin, has been used as a thermal conducting sheet to transfer heat generated from an electronic device or element to a heat sink (Patent Document 1).
Such a thermal conducting sheet requires low hardness because the sheet needs to be in close contact with an electronic device or element, which is a heat generator, with a gap as small as possible, while no weight is applied on the sheet. However, the low hardness of the sheet hinders a good handling of the sheet and deters shape recovery of the sheet after compressive deformation. Thus, there may be a problem of losing close contact with a heat generator or a heat sink.
Therefore, a thermal conducting sheet of a configuration, in which a thin sheet for reinforcement is adhered on a low-hardness sheet, has been proposed (Patent Document 2). It is expected that the thin sheet imparts strength to such a thermal conducting sheet, resulting in better handling and suppressing excessive compressive deformation of the low-hardness sheet.